Jacob Samuel, Kallikourdis Antonios, Sellke Frank, Dunning Joel
Department of Cardio-thoracic Surgery, Aberdeen Royal Infirmary, Aberdeen, AB25 2ZN, UK.
Interact Cardiovasc Thorac Surg. 2008 May;7(3):491-8. doi: 10.1510/icvts.2008.178343. Epub 2008 Mar 13.
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether blood cardioplegia is clinically superior to crystalloid cardioplegia for myocardial protection. Altogether 501 papers were identified. We selected 22 papers that represented the best evidence to answer the question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. This is a difficult topic to review, as the techniques studied in the many trials performed vary widely. Factors which may vary include warm or cold blood cardioplegia, antegrade and retrograde administration, systemic hypothermia or normothermia, topical heart cooling, high and low potassium solutions, 'hot shots', warm induction, volume of cardioplegia, patient factors and bypass times. However, three papers stand out. The meta-analysis of 34 randomised trials by Prof Fremes (2006) found a significantly lower incidence of low output syndrome (LOS) and CK-MB release with blood cardioplegia. He found no differences in myocardial infarction or mortality. This meta-analysis was confounded, however, by the fact that he was unable to extract data on LOS and CK-MB from the two largest trials which contributed over half the patients in his paper and are significantly larger than all other studies. The first paper by Ovrum (2006) randomised 1440 patients to antegrade cold blood or crystalloid and found no clinical differences, and the second paper by Martin (1994) of 1001 patients compared warm blood to cold crystalloid but the study had to be stopped due to a high incidence of neurological events in the warm blood group. We reviewed a further 18 randomised trials reporting over 50 patients. Of these, 10 reported some statistically significant clinical outcomes in favour of blood cardioplegia and five reported statistically significant differences in enzyme release in favour of blood cardioplegia. A recent survey of UK practice found that 56% of surgeons use cold blood cardioplegia, 14% use warm blood cardioplegia, 14% use crystalloid cardioplegia, 21% use retrograde infusion and 16% do not use any cardioplegia. The papers presented in our review support most of these practices!
一篇心脏外科领域的最佳证据主题文章是按照结构化方案撰写的。所探讨的问题是血液停搏液在心肌保护方面在临床上是否优于晶体停搏液。共识别出501篇论文。我们挑选了22篇论文，它们代表了回答该问题的最佳证据。这些论文的作者、期刊、发表日期和国家、所研究的患者群体、研究类型、相关结局及结果均列于表格中。这是一个难以综述的主题，因为众多试验中所研究的技术差异很大。可能存在差异的因素包括温血或冷血停搏液、顺行和逆行给药、全身低温或正常体温、局部心脏降温、高钾和低钾溶液、“热射液”、温诱导、停搏液容量、患者因素及体外循环时间。然而，有三篇论文较为突出。弗雷姆斯教授（2006年）对34项随机试验的荟萃分析发现，使用血液停搏液时低心排血量综合征（LOS）和肌酸激酶同工酶（CK-MB）释放的发生率显著更低。他发现心肌梗死或死亡率方面没有差异。然而，该荟萃分析受到了干扰，因为他无法从两项最大的试验中提取关于LOS和CK-MB的数据，而这两项试验贡献了他论文中超过一半的患者，且规模明显大于所有其他研究。奥夫鲁姆（2006年）的第一篇论文将1440例患者随机分为顺行冷血或晶体停搏液组，未发现临床差异，马丁（1994年）的第二篇论文对1001例患者进行了温血与冷晶体停搏液的比较，但该研究因温血组神经事件发生率高而不得不停止。我们还回顾了另外18项报告患者超过50例的随机试验。其中，10项报告了一些在统计学上支持血液停搏液的显著临床结局，5项报告了在酶释放方面支持血液停搏液的统计学显著差异。最近一项关于英国实践的调查发现，56%的外科医生使用冷血停搏液，14%使用温血停搏液，14%使用晶体停搏液，21%使用逆行灌注，16%不使用任何停搏液。我们综述中呈现的论文支持了这些实践中的大多数！
